Sounds like every 2 months you get a dump of data and reload it. Correct me if thats wrong.
Will the association ids("assignee_id": "8ce825a978eebf26ad2c13de6e370bb3") remain the same across data loads?
I performed a search for patents with assignee_id 8ce825a978eebf26ad2c13de6e370bb3 which worked as expected with every patent returned having the specified assignee.
On the next data load will "Commonwealth Scientific & Industrial Research Organization" have the same assignee_id?